[enh] paging support for stackoverflow

categories = ['it']

url = 'http://stackoverflow.com/'

search_url = url+'search?'

search_url = url+'search?{query}&page={pageno}'

result_xpath = './/div[@class="excerpt"]//text()'

paging = True

def request(query, params):

    params['url'] = search_url + urlencode({'q': query})

    params['url'] = search_url.format(query=urlencode({'q': query}),

                                      pageno=params['pageno'])

    return params